Fig. 4: Comparison between GD and steering neurons.
From: Neural representation of goal direction in the monarch butterfly brain
a, b Change in angular tuning of steering neurons to compass perturbations (a) and aversive conditioning (b). Neurons were ordered according to their pfds before compass perturbations and conditioning. Each neuron’s firing rate (FR) is normalized against its peak firing rate. Box plots show the ratio between changes in pfds and changes in heading evoked by compass perturbations (p = 0.0003, U = 65, a) and conditioning (p = 0.0003, U = 65, b) in steering (magenta, n = 19) and GD neurons (blue, n = 20) (two-sided Mann–Whitney U test). Values close to one indicate a strong association between angular tuning and behavior. c, d (Left) Example traces comparing heading (top) and neural firing rate (bottom) of a steering (c) and a GD neuron (d). Dots indicate time points of behavioral turns. (Right) Sliding averages (top, shaded areas represent percentile) and raster plots (bottom) summarizing the firing rates of one steering (c) and one GD neuron (d) in relation to behavioral turns at time = 0 (dashed line). e Directional selectivity of steering (top, n = 16) and GD (bottom, n = 14) neurons. Respectively, positive and negative values indicate stronger response preceding counterclockwise or clockwise turns. f (Left) Comparison of the firing rate of simultaneously recorded steering (magenta trace) and GD (blue trace) neurons during a flight turn (black trace). (Right) GD neurons modulated their firing rate prior to steering neurons (p = 0.005, W = −85, n = 14 pairs of simultaneously recorded neurons; two-sided Wilcoxon matched-pairs signed-rank test). g Pfds of steering (magenta), GD (blue), and HD neurons (green) relative to the butterflies’ goal direction (0°). The mean pfd is shown as black line, the sectors represent the 95% confidence intervals. The p-values refer to the statistics from the Rayleigh test. Box plots in (a), (b), (f) indicate medians (middle line), 25th, 75th percentiles (boxes) and 5th and 95th percentile (whiskers). Source data file: datasource.xlsx Fig. 4.
